Nutritional Needs After Gastrointestinal Surgery

GIST Support International posed questions about the nutritional needs of GIST patients after gastrointestinal tract surgery to two surgeons: N. Joseph Espat, MD, FACS and Ponnandai S. Somasundar, MD, FACS.

Dr. Espat is Professor and Chief, Surgical Oncology, and Vice-Chair of Surgery at Roger Williams Medical Center in Providence, Rhode Island. He previously served as Interim Chief of Surgery, Chief of Hepatobiliary Surgery, and Director of Regional Hepatic Therapies at the University of Illinois at Chicago. Dr. Espat also holds a Master’s degree in nutrition and has published extensive research concerning nutritional needs of surgical patients. His clinical interests include hepatic tumors, complex pancreatic diseases and energy-based technology development for tumor ablation.

Dr. Somasundar is Assistant Professor of Surgery, Boston University; Surgical Oncologist, Roger Williams Medical Center in Providence, Rhode Island; and Director of Oncology, Kent County Hospital. His clinical interests include advanced laparoscopic surgery for foregut tumors (liver, pancreas) and surgical education.

Below are the responses of Dr. Somasundar and Dr. Espat to our questions.

1. What are the effects of partial gastrectomy versus total gastrectomy on the body’s ability to absorb nutrients?

Post-gastrectomy syndromes entail nutritional intolerances and deficiencies.

The intolerances include:

  • dumping syndrome [see question 5 for more information],
  • fat maldigestion [the inability to enzymatically break down dietary fats (long-chain triglycerides) into smaller molecules (diglycerides and free fatty acids) that are better absorbed by the small intestine]
  • gastric stasis [Post-surgically the remaining stomach may lose its normal muscular motility. This hampers the digestive processes that normally occur in the stomach. Also the stomach may not empty properly.]
  • lactose intolerance [the inability to digest lactose, the sugar found in dairy products. Typically this is caused by a lack of the enzyme lactase in the small intestine. Approximately 70% of the world’s population is naturally lactose intolerant by adolescence. Chronic disease and disruption of normal digestive processes (by gastrointestinal surgery for example) can result in lactose intolerance in a normally tolerant person.]

Dumping syndrome and fat maldigestion are more severe with total gastrectomy than with partial gastrectomy. Dumping syndrome improves with time.

The deficiencies include:

  • Nutritional anemias due to vitamin B12, folate or iron deficiency are common in gastrectomized patient. Total gastrectomy patients by design have megaloblastic anemia secondary to intrinsic factor deficiency in 100% of the patients. The most common anemia that they develop is iron deficiency anemia.
  • metabolic bone disease. There is increased incidence of fractures. [Normal calcium blood levels are vitally important for the functioning of many cells, especially muscle cells. The body’s largest storage area for calcium is the bony skeleton. When there is a lack of dietary calcium, from either calcium malabsorption due to pathologic processes or Vitamin D deficiency or from a calcium-deficient diet, the body will take calcium from the bones in order to keep blood calcium levels adequate for normal function. Over a long period of time, enough calcium can be absorbed from the bones such that they are susceptible to fracture.]

2. What is the impact on nutrient absorption of any surgery that eliminates bile from reaching the GI tract?

Bile is made in the liver. It consists of cholesterol, bile salts, and bilirubin. It disperses fat globules into smaller droplets, assisting with lipid (fat) digestion. Bile is reabsorbed through ileum and returned to liver via portal vein. The lack of bile results in fat malabsorption and fat-soluble vitamin deficiency. The fat soluble vitamins are A, D, E and K.

3. What is the impact on nutrient absorption of surgery that reduces or prevents pancreatic enzymes from reaching the GI tract? Are supplemental enzymes needed?

The pancreatic enzymes are necessary for digestion. These enzymes from the pancreas are necessary to break down protein, fat, and carbohydrates in foods that are ingested. When there is a deficiency of these enzymes, nutrients are not broken down, resulting in malnutrition and weight loss. This condition is called malabsorption because the intestine is unable to absorb these vital nutrients. The two major symptoms are diarrhea (frequently with fat droplets in the stool) and weight loss. Pancreatic enzymes can be taken by mouth to replace those that are no longer made by the pancreas.

4. Is there any major nutritional impact from surgical removal of a segment of small intestine?

There is no impact on surgical removal of a small segment of small intestine. The impact becomes visible only if less than 150cm of small intestine is left behind after resection. The presence of ileo-cecal valve (between the small bowel and the colon) plays a major role in preventing the patient from having effects of lack of small bowel. [Losing more than 2/3’s of one’s small intestine in surgery may result in "Short Bowel Syndrome" where there is not enough surface area left in the remaining bowel to absorb an adequate amount of nutrients for normal life. After eating, the patient may have symptoms of abdominal distress (vomiting, diarrhea, bloating) and over time may develop deficiencies of many vitamins, minerals and calories.]

5. What is early gastric emptying (dumping syndrome), and how can it be prevented or reduced?

Dumping syndrome is of two varieties: early dumping and late dumping. Early dumping occurs about 15-30 minutes after ingesting a meal and is evidenced by diarrhea, fullness, and abdominal cramps and vomiting. Late dumping presents two to three hours after eating and results in weakness, sweating, nausea, hunger and anxiety. Late dumping is thought to be the result of reactive hypoglycemia. Foods and liquids with high sugar content may exacerbate symptoms of both early and late dumping syndrome.
To prevent dumping syndrome, use these strategies:

  • Eat 6 small meals per day.
  • Eat slowly and chew all foods thoroughly.
  • Sit upright while eating.
  • Limit fluid consumption while eating meals.
  • Eat meals containing protein and high fiber content.

6. What causes nausea and vomiting after gastrectomy, and how can these problems be reduced?

The reservoir is small, and hence eating a large meal may give rise to nausea and vomiting. A high sugar content meal could also result in nausea and vomiting. In that case avoid juice, soda, ensure, Boost-type drinks, cakes, pies, candy,doughnuts, cookies, fruits cooked or canned with sugar, honey, jams, and jellies.

7. What are sensible eating strategies after GI tract surgery?

  • Eat 5- 6 small meals a day.
  • Avoid too much fat.
  • Avoid high sugar content.

8. Might all patients benefit from supplemental nutrients (including vitamins and minerals) following GI tract surgery?

Not all patients would benefit from supplemental nutrients. We do not supplement everybody after a small bowel resection or colon resection. However patients with gastric surgery or pancreatic surgery may benefit from supplemental nutrients to replenish and restore the nutrients to the normal levels.


For a free-access detailed paper on post-surgical nutrition by Dr. Espat and co-authors, link to the following paper. Although it directly concerns patients undergoing the Whipple procedure or pancreaticoduodenectomy, it is generally relevant to patients with other GI tract surgeries.

Zgodzinski W, Dekoj T, Espat NJ.
Understanding clinical issues in postoperative nutrition after pancreaticoduodenectomy.
Nutr Clin Pract. 2005 Dec;20(6):654-61. Review. PMID: 16306303

Click the above link to see the abstract in PubMed, then click the Sage Publications icon to view the full paper.